Help with double/dual range sliders

Hi all,

I’m trying to use a dual range slider in a “Leasing Simulator”, but I simply couldn’t figure out how to make the second slider to show a % value that amounts the total to a 100%
I believe that if you see the example you will quickly understand what i’m trying to do.
See it live
Dual_range_slider.rp (591.7 KB)
I’m trying to do something similar to the simulator at the end of this page:

Appreciate any help